Tasman Lake is a proglacial lake formed by the recent retreat of the Tasman Glacier in New Zealand's South Island. In the early 1970s, there were several small meltwater ponds on the Tasman Glacier. By 1990, these ponds had merged into Tasman Lake. Tasman Lake has quickened the retreat of the Tasman Glacier. Initially it did so by undercutting the cliff at the end of the glacier, causing parts of the cliff to fall into the lake. Since 2006, however, a 50–60 m (160–200 ft) apron of submerged glacial ice projects out from the cliff, and icebergs periodically break off the apron and float away down the lake. Because more of the glacier is now in contact with the water, its rate of retreat has increased. By 2008 the lake was about 7 km (4 mi) long, 2 km (1 mi) wide and 245 m (800 ft) deep, having almost doubled in area since 2000. It is expected to grow to a maximum length of about 16 km (9.9 mi) within the next one or two decades. (Source: Wikipedia.org, CC BY-SA)